The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 15, 2000
Filed:
May. 12, 1999
Takashi Fuse, Kawasaki, JP;
Youji Nishiyama, Kawasaki, JP;
Yoshitaka Oshima, Kawasaki, JP;
Fumiyuki Takahashi, Kawasaki, JP;
Hiroyuki Tsukahara, Kawasaki, JP;
Fujitsu Limited, Kawasaki, JP;
Abstract
The bump height is measure din a sample area on a wafer, the bump height distribution on the wafer is estimated on the bases of the measured value, the portion where the estimated height distribution is out of a predetermined range is determined as an inspection area, and the bump height is measured in the inspection area, and a chip area having a bump height out of a predetermined range is judged to be defective. Data of the inspection areas and inspection results are accumulated, and the inspection density is renewed on the basis of the accumulated data. In another method, the inspection area is divided into rectangular blocks so that each block has a width of approximately equal to a light beam scanning length and a distance between any adjacent bumps in the feeding direction is less than a predetermined value, feeding path being perpendicular to the scanning direction. Block feed time and between-block feed time are calculated, a whole feeding path whose total feed time of the block and between-block feed time are minimum is found, and bump height is measured with receiving reflected light from the bump while feeding along the found feeding path.